Emily Herring Pender County Livestock Agent
Materials Needed: Plastic Bucket (any size) CLEAN! Soil Probe or Shovel Stainless Steel or Chrome-plated Soil Boxes & Soil Sheet (from Extension Office) Pen TIME!!! *Avoid brass or galvanized tools*
Observe area to be sampled No more than 10 acres per box Keep like soils together Example: wet spot in field, sandy ridge, Fence row, or tree line Use soil probe to collect cores 8 inches for establishing 4 inches for maintaining (root zone) Take 15 random samples per site Dump like samples in bucket & mix Write info on box, fill up to fill line (2/3 box) Fill out/attach sheet to box and mail together
Purpose: prevent fertility from being a yield-limiting factor ( used for all crops) Tests 22 factors of soil: Soil acidity & level of nutrients v/s nutrients needed by plant grown Lime Tenths of Tons per acre needed (anything below 0.3 tons/acre soil test indicates no lime is needed) Nitrogen (N) - pounds/acre needed
HM% - organic matter in soil W / V (weight per volume) soil texture CEC Cationic Exchange Capacity extent soil can hold nutrients ph- acidity in soil P,K, Mn, S, Zn & Cu index 0 to 100 0 to 25 and below low fertility 25 to 50 Medium 50 to 100 high 250+ could be detrimental to crop (applying too many nutrients!)
Lime is the anti-acid for soils ph Lime NC soils - acidic (low ph) and need lime. -general rule every 3 years -3 to 6 months before planting -incorporate (mix into soil) Amount Needed = crop needs (target ph), soil type & current soil fertility
Promotes healthy root development, enhances plant's ability to survive dry weather Supplies needed Ca and Mg Promotes more efficient use of phosphorous supplied by fertilizer Improves use of some herbicides
Factors that decrease soil ph Rainfall leaching of nutrients from soil (decrease in Ca and Mg that lime supplies) Plants utilize nutrients from soil Decay of crops or animal waste in field Use of fertilizers and nitrogen
Target ph- ph your plant needs Some crops can not tolerate low ph Bermudagrass 6.5 Est. 6.5 Maint. Fescue 6.5 Est. 6.0 Maint. Rye 6.0
Calcitic Lime and Dolmitic Lime Calcitic- Calcium Carbonate Dolmitic Calcium Carbonate and magnesium carbonates Example: dolmitic lime is used when soils are Mg defficient (most of NC) What about gypsum?
20-30 mesh is the largest Reacts slowly May not ever reach target ph 100 mesh is the smallest Reacts quickly Highest ph reached Best method is to have a range in particle size
Ag Lime- 90% passes through 20 mesh Dolomitic Lime- 35% passes through 100 mesh Calcitic- 25% must pass through 100 mesh No specific CCE; label specifies lime needed to give 90% CCE standard ag lime Agriculture Lime Calcium Carbonate Equivalent 80% Passing 20 mesh screen 90% Passing 100 mesh screen 30% (2250 pounds of this material equals 1 ton of standard agricultural liming material)
Can be applied any time Not very water soluble Moisture is important in chemical reaction Apply full rate if you incorporate into soil If surfaced applied apply up to 1.5 tons every 6-9 months until full rate is applied Extremely low ph; consider renovating pastures Avoid long term no-til unless you have adequate ph
ph and availability is interrelated Iron, Manganese, Zinc, and sometimes Copper More difficult to correct
If high ph Sample 0-4 inches; 4-8 inches; 8-12 inches If lower ph exists in top 12 inches, deep tillage can be recommended But caution; could bury fertile topsoil Consider alternative crops/plants Apply organic matter like pine bark/pine needles Apply elemental S (90% S)
Caustic=Protect eyes and skin Powder or granular products Slow to react Mix with soil for best results Rate is determine by trial and error Apply and resample in 3 months
After application of lime; plants turn yellow Low manganese is usually the problem Lime increase ph therefore reducing availability of manganese Apply manganese to fields to get increase in productivity in crop. Yield will pay off in the long run to cover cost of lime and manganese.